Angular dependent magnetothermopower of alpha-(ET)2KHg(SCN)4

TL;DR

This study investigates the angular dependence of magnetothermopower and Nernst effect in alpha-(ET)2KHg(SCN)4, combining experimental measurements with a theoretical model involving magnetic breakdown between different electronic bands.

Contribution

It introduces a theoretical model based on magnetic breakdown to explain the angular-dependent thermoelectric phenomena in alpha-(ET)2KHg(SCN)4, supported by experimental data.

Findings

Quantum oscillations originate only from the alpha orbit.

Properties in the CDW state are mainly influenced by new open Fermi sheets.

Theoretical model successfully simulates the experimental data.

Abstract

The magnetic field and angular dependencies of the thermopower and Nernst effect of the quasi-two-dimensional organic conductor alpha-(ET)2KHg(SCN)4 are experimentally measured at temperatures below (4 K) and above (9 K) the transition temperature to fields of In addition, a theoretical model which involves a magnetic breakdown effect between the q1D and q2D bands is proposed in order to simulate the data. Analysis of the background components of the thermopower and Nernst effect imply that at low temperatures, in the CDW state, the properties of alpha-(ET)2KHg(SCN)4 are determined mostly by the orbits on the new open Fermi sheets. Quantum oscillations observed in the both thermoelectric effects, at fields above 8 T, originate only from the alpha orbit.